Being busy, we try to squeeze in as much gasoline as possible to stretch out our trips to the gas station. But topping off after the gas pump automatically shuts off is a bad idea. There are two very important reasons why topping off is bad for you and the environment.

When the automatic shutoff occurs, your tank has the right amount of gasoline. If you put more gasoline in the tank, some of the gasoline may get into the carbon filter – this component is only supposed to carry fumes. This will not destroy your car. But over time, it can result in lower mileage, higher emissions, and unnecessary repairs. This is bad for your pocketbook, and bad for the environment. Don’t over fill. You’ll keep the Bay Area a bit less smoggy.

When you continue to top off your fuel tank after the automatic shutoff, there is a possibility that the extra gasoline will spill out. Three reasons why this is bad:

You are spilling money on the ground – literally.

Gasoline runoff goes into the ground, into the air and into the storm water system. No fuel spill is good for anything alive.

Gasoline fumes are bad for you – topping off and spilling that stuff makes it more likely you will breathe the fumes. In extreme cases fuel spills at filling stations can become fire or explosion hazards.

So next time you are at the gas station – let the automatic shutoff do its job – save your money and save the environment.